An Introduction of Chang’E-4 Probe:Probe（Lander,Rover）+ Relay StatelliteSoft-landing on lunar farsideLanding and roving explorationWill be launched between 2018 and 2019

the probe:Chang’E-4 probe，lander and rover have the same technical status with the Chang’E -3; but exploration will be redesigned; the payload will be reconfigered; The name of the probe might be changed.Chang’E-4 probe is a backup spacecraft of Chang’E -3 probe. By now, all platform products of the probe have been manufactured, waiting for further AIT.The probe will be launched by a long March 3B rocket from the Xichang Statellite Launch Center(XSLC) which is the same way with the Chang'E-3 between 2018 and 2019

The relay statellite:will be first launched into a lunar transfer orbit about the end of 2018 in the whole mission, then starts its earth-to-moon jurnery alone, and will enter and run in a Halo orbit around the Earth-Moon L2 point; the design life is 3 years.would provide relay service for the probe and the Earth, and carry out exploration.

Engineering objectives are as follow. To realize the first soft landing on the lunar farside and perform exploration in human history. To demonstrate technologies of lunar data relay, landing and roving on complicated terrains of the lunar farside, and lunar night power generation; To perform further detailed survey on lunar environment in order to lay a foundation for subsequent lunar exploration mission.

there is a puzzle news:http://www.cnsa.gov.cn/n1081/n7529/n308608/725881.html中欧深空探测研讨会在北京召开发布日期：2015年07月14日 字体：【大】【中】【小】 2015年7月9日至10日，中国国家航天局与欧洲空间局在京召开中欧月球探测研讨会，会议围绕嫦娥四号目标任务和有效载荷搭载进行了讨论。 会上，欧洲空间局相关专家提出利用嫦娥四号搭载月震仪、快闪相机、激光反射器等载荷的建议。经商议，双方初步确定将月震仪和快闪相机等四个有效载荷纳入合作范围。欧洲空间局负责协商欧洲载荷以及其总成与接口，中方通过双边航天局长会晤推动建立载荷研制国技术团队，争取在2018年提交正样。 来自法国巴黎索邦大学、瑞士苏黎世理工、澳门科技大学以及中国国家航天局探月与航天工程中心、中国科学院、北京大学、中国科学技术大学、中国地质大学等单位的专家学者参加了会议。

laser reflector, it means Chang'e 4 will be landed on nearside, What will happened?

Juramike

Jul 15 2015, 01:49 PM

(Edited!)

Phil Stooke

Jul 15 2015, 03:52 PM

The current Chinese plan is to land on the far side. The laser reflector is suggested as a high priority payload by an ESA group looking at cooperation. The two don't work together, so we don't know which way it will go. But it's not a contradictory plan, it's an external suggestion to change the plan. Probably won't happen, because the prestige (and science value) of the first far side landing is likely to trump that one payload suggestion.

Incidentally, there's really no reason why that laser reflector shouldn't be mounted on the landing stage of the Chang'E 5 sample return lander, which will be near side. That's a far more likely outcome than flying it on CE4.

This refers probably to the micro-reflector array INRRI (Instrument for landing-Roving laser Retroreflectors Investigations). INRRI has been sized to give the right signal for LOLA (Lunar Orbiter Laser Altimeter) on LRO. By the way, one INRRI was mounted on EDM Schiaparelli as long-time scientific asset.

Thorsten Denk

Jan 14 2016, 01:39 PM

It seems that Cháng'é 4 will go to the lunar farside end of 2018!

QUOTE

SinoDefence ‏@SinoDefenceChang'e 4 mission given goahead. Relay sat in Jun 18, followed by landing on Moon far side in late 2018.

A fascinating new paper is now online - Wang and Liu (2016), A Chang’e-4 mission concept and vision of future Chinese lunar exploration activities, Acta Astronautica (available online 11 JUne 2016). If you have access!

It suggests that Apollo basin is the most likely target but other farside basins are possible. Also looks ahead to future missions, including a suggestion that a robotic station could be built up, possibly as a precursor to human flights. From 3 to 5 landers near the south pole, carrying between them up to a dozen rovers, to build the station, which has obvious echoes of ESA's robotic lunar village.

This is on the flat floor of the large crater Von Karman, with a bit of ejecta from the relatively young crater Finsen. Until now most indications had been for a landing near the Apollo basin at about 42 south, 157 west (203 east).

I take it Von Karman's walls are sufficiently lofty to be visible in any surface imagery taken from inside that box?

p

Explorer1

Jun 12 2017, 05:35 AM

I wouldn't be so sure; the horizon is really close in the Chang'E 3 surface images. We shouldn't expect huge vistas anymore than we get them on Mars; cool terrain is by definition hazardous!I would welcome being pleasant surprised to see anything more than a few km away, of course.

Phil Stooke

Jun 12 2017, 05:16 PM

Short answer - I think some relief will be visible. Von Karman is about 3500 m deep and some distant topography should show up.

I will post something on the Chang'E 3 thread about distant topography. There are distant hills to the north and west at distances of 10 to 15 km, protruding above closer topography. To the east the horizon is about 4 km from the lander.

Phil

EDIT: OK, I posted in the other thread. That was a very flat site, but local high spots can be seen about 10 km away. I would expect that either the central peak of Von Karman or the SE wall of the crater should be visible from the lander, and possibly both will be, as well as small crater rims closer to the landing site. Not high mountains like Taurus-Littrow, but distant features should be visible, appearing as low hills.

shows a number of sites at about 45 degrees north or south. I am preparing something on this topic, so I will post a map later. Some sites are in mare-type areas of the SPA basin or the large craters in that area, but the northern sites are all in or between large craters in the highlands (Mare Moscoviense is not one of these areas).

This is from a presentation at the German Aerospace Centre DLR, where China and Germany have just agreed to cooperate on the mission, Germany joining several other countries.

Probably everyone knows this, but on the Moon, the horizon is inherently closer than from a similar vantage point on Earth or Mars. Though the bowl of a crater may make the global curvature locally moot.

Phil Stooke

Jul 7 2017, 06:00 PM

That's true, of course, but the distance to the ideal horizon is not as important as the height and distance of significant relief features. Von Karman is about 160 km across and up to 4 km deep (wall height varies quite a bit). A good comparison might be with Flamsteed P, the flooded crater which Surveyor 1 landed in. It is 80 km across, but mostly filled with lava and with hills 1500 m high protruding above the plains. Hills 20 km away were visible in the Surveyor 1 panorama. Scaling up, I am confident there will be some relief on the CE4 horizon. Maybe if the landing is in exactly the worst place for viewing relief there would not be much, but from many areas some features will be visible.

Phil

Phil Stooke

Feb 27 2018, 07:49 PM

The Von Karman site may not be the final word on site selection... it was identified in a paper in 2017, but two papers by Jia et al. in 2018 (one in the Chinese Journal for Deep Space Exploration, the other in Planetary and Space Science, essentially the same content) prefer the site numbered S5 in the map a few posts above. It is south of the Apollo basin and closer to the centre of the SPA basin than any other of those mapped sites. I think all we have right now is competing suggestions, and the final target may still be uncertain.

Phil

Phil Stooke

Mar 18 2018, 06:09 PM

I'm at the Microsymposium just prior to LPSC. It just concluded, with presentations on the Chang'E program and others. Specifically for this thread, Von Karman seemed to be the likely site again - Apollo was promoted as a good site but probably for a future mission.

Concerning the notification of the recruitment of the No. 4 relay star nameArticle Source: Release Time:2018-03-29 All relevant units:

The fourth relay satellite will be launched in May 2018. Considering that the No. 4 mission will be the biggest bright spot in China's aerospace field in 2018, to further establish a good image of the lunar exploration project and expand the influence of the project, the Lunar Exploration and Space Engineering Center plans to use the project implementation unit as the main target for solicitation of No. 4 Relay star name.

The No. 4 relay star name collection activity will take place from March 27 to April 15, 2018. The names so collected should reflect the theme of lunar exploration, have innovative and significant technological and cultural characteristics, be positive, and conform to the socialist core values.

Specially invited your organization to participate in this solicitation. Please refer to the attachment for specific requirements.

Attachment: Program for Selection of Relay No. 4 Relay Stars

Moon Exploration and Aerospace Engineering Center

March 27, 2018

Phil Stooke

Apr 22 2018, 06:20 PM

This link is to the current issue of China's Journal of Deep Space Exploration:

A very interesting set of papers about the CE4 landing site including several suggestions for landing sites and even rover traverse routes. Chinese language with English abstract, but Google document translation will help, and the illustrations carry a lot of information even without translation. Many of these papers will probably appear in English elsewhere at a later date. I can feel a map coming on...

Phil

Phil Stooke

Apr 23 2018, 11:48 PM

After a suitable gestation period, here is a map of the sites suggested for Chang'E 4 in Von Karman crater. The references are from the previous post except the mention of Snape et al. (2010) which is an LPSC abstract, easy to search for if you need it. THe bottom map includes possible traverses suggested by Mou et al. (2018)

China Securities News reported on April 24 from the National Bureau of Science, Technology, and Technology that during the opening ceremony of the "China Aerospace Day" home event in 2018, Wu Yanhua said that the Chang'e 4 is one of the major tasks for China's space industry this year...

Wu Yanhua announced at the opening ceremony that the No. 4 relay star was named "Bianqiao" and the two small satellites were named "Longjiang No. 1" and "Longjiang No. 2".

Phil

Phil Stooke

Apr 24 2018, 09:39 PM

Interesting that Google translates that website to give the relay satellite name 'Bianqiao', but all other sources - AND using Google to translate just the characters for that name, give 'Queqiao'. The names mean Magpie Bridge (relay) and Dragon River (the two small satellites), and there are numerous tweets and stories out there today giving the background.

Late in the year we will presumably get a name for the new rover.

Phil

Phil Stooke

May 20 2018, 10:08 PM

The relay satellite was just launched successfully.

Phil

nprev

May 20 2018, 10:23 PM

Ah, thanks, Phil! Was wondering; didn't seem to be a live feed available anywhere.

Explorer1

May 20 2018, 10:29 PM

Someone at the site pointed their phone at a screen, and streamed it out via a Chinese media platform; looks like the micro-satellites also separated successfully.

It seems all is well with our new mission - the relay satellite has passed the Moon and is on its way to its L2 halo orbit. The two little moon orbiters are in lunar orbit. Hoping for an image or two from the Saudi camera on one of them.

Phil

Phil Stooke

May 27 2018, 09:56 PM

Twitter: Jonathan McDowell @planet4589 2 hours ago

So it looks like Longjiang-2 (DSLWP- is in a 350 x 13800 km x 21 deg lunar orbit. Longjiang-1 seems to have failed on May 21 and presumably remains in distant Earth orbit following its lunar flyby------------------

I spoke prematurely in my last post - all seems well with the other two spacecraft but Longjiang 1 failed. The small camera is on Longjiang 2. I see some reports that radio enthusiasts will be able to download images from the camera, but I don't know the details yet.

Andrew Jones (https://twitter.com/AJ_FI) reports some new images from the Saudi camera. EDIT - Andrew has just pointed out to me that the image is not from the Saudi camera, but from a second camera which I was not aware of or had forgotten about. This was developed by students in China.

One, which I assume is a mosaic of many image strips, covers Mare Nubium. This shows the image coverage on a background from LRO Quickmap.